October 2020 General Discussions & Observations Thread

[bluewave]

12 minutes ago, LibertyBell said:

Okay so according to the second key point, there are suites of the GFS run without the GFDL?  Why dont we just use those?  Or if there aren't, why not make a para GFS that doesn't use GFDL microphysics and run that parallel to the current GFS and we can compare them to each other and give preference to the one that's more accurate?

 

It looks like they ran tests without the GFDL microphysics and determined that it was the cause of the cold bias. I am not sure if the new parallel GFS is running one of those suites. Maybe we will get a statement from them once the new parallel becomes operational. 

[Santa Claus]

absolutely premium weather outside.  not quite indian summer but close.  bright blue sky, warm sun and breeze.  this is a long stretch of mostly uninterrupted great weather a la SoCal.  week after week of gorgeousness.  i almost wish i played golf.

[Dark Star]

1 hour ago, Will - Rutgers said:

absolutely premium weather outside.  not quite indian summer but close.  bright blue sky, warm sun and breeze.  this is a long stretch of mostly uninterrupted great weather a la SoCal.  week after week of gorgeousness.  i almost wish i played golf.

Almost...

[donsutherland1]

Temperatures rose into the middle and upper 60s and even lower 70s in parts of the region today under bright sunshine. Tomorrow will be a little warmer with temperatures rising into the lower 70s across a large part of the region.

Out west, Phoenix recorded its 144th day on which the temperature rose to 100° or above. That surpassed the previous annual record of 143 days, which was set in 1989.

Generally above normal temperatures will prevail through mid-month. By mid-month, New York City will likely have an October 1-15 mean temperature above 60° and the region will likely see temperatures running an overall 1°-3° above normal. Afterward, a brief period of cooler than normal to near normal temperatures could develop. The potential exists for a fairly sharp shot of cold just after mid-month. However, milder conditions will return shortly afterward.

The ENSO Region 1+2 anomaly was -1.2°C and the Region 3.4 anomaly was -1.2°C for the week centered around October 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.92°C and the ENSO Region 3.4 anomaly has averaged -1.00°C. La Niña conditions will likely prevail into at least the start of winter.

The SOI was -2.26.

Today, the preliminary Arctic Oscillation (AO) figure was -0.301.

On October 13 the MJO was in Phase 4 at an amplitude of 1.987 (RMM). The October 12-adjusted amplitude was 1.911.

Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO.

In addition, from the larger pool of La Niña winters following El Niño winters, there were four cases where October saw the MJO in Phases 4-6 for 20 days or more: 1983-84, 1988-89, 1998-99, and 2016-17. All four cases featured an EPO+/AO+ winter. Three cases saw the MJO in Phases 4-6 for less than 20 days: 1995-96: 12 days, 2007-08: 6 days, and 2010-11: 6 days. Both 1995-96 and 2010-11 featured a predominantly negative AO. The latest ensemble guidance favors October 2020 falling into the former pool.

Based on sensitivity analysis applied to the latest guidance, there is an implied 70% probability that New York City will have a warmer than normal October. October will likely finish with a mean temperature near 58.3°.   

 

[gravitylover]

4 hours ago, Will - Rutgers said:

absolutely premium weather outside.  not quite indian summer but close.  bright blue sky, warm sun and breeze.  this is a long stretch of mostly uninterrupted great weather a la SoCal.  week after week of gorgeousness.  i almost wish i played golf.

Ya know that's a good idea. Now I know what I'm doing tomorrow.

[SACRUS]

 

10/14

ACY: 72
PHL: 72
LGA: 71
New Brnswck: 71
EWR: 71
BLM: 71
TEB: 70
JFK: 69
TTN: 69
ISP: 67
NYC: 67
 

[CIK62]

The next 8 days are averaging 62degs.     Making it 57degs., or about +1.0.

BN period that  was suppose  to start the 17th. will be brief.     The BN period set for the 21st.-----becomes the 25th. now and record heat for the 22nd. sneaks in?      Models S_CK!      At any rate, one must bet that the last 5 days of the month will have cold, rain, sleet and wind----in some yet unknown atmospheric concoction.

About 1" rain for tomorrow/Saturday early.    GEM has just 0.2".

September was hottest one in history they say.

59*(80%RH) here at 6am.        64*(74%RH) by 11am.      65* by 1pm.        Never got past 66*(4pm-5pm) with the south wind and filtered sun around here.

[bluewave]

GEFS in full cold bias correction mode as its seeing the stronger WAR pattern. Tough to bet against those very warm SSTs to our east. This is how a -5 forecast for the start of the month turned into a +1 to +3.

 

 

[frd]

50 minutes ago, bluewave said:

GEFS in full cold bias correction mode as its seeing the stronger WAR pattern. Tough to bet against those very warm SSTs to our east. This is how a -5 forecast for the start of the month turned into a +1 to +3.

This has been ongoing the last several Fall seasons. I believe you posted something about the WAR and the Western periphery is where you will find many late record high temps, especially in Virginia down to Florida.  The warm SSTs certainly are a factor along the immediate coastal plain and even further inland.     

[bluewave]

7 minutes ago, frd said:

This has been ongoing the last several Fall seasons. I believe you posted something about the WAR and the Western periphery is where you will find many late record high temps, especially in Virginia down to Florida.  The warm SSTs certainly are a factor along the immediate coastal plain and even further inland.     

We are on track for an 11th consecutive warmer than normal October.

 

Oct.......EWR...NYC...LGA

2020..+1.0...+0.9....+1.6...through the 14th

2019..+3.8...+3.0 ...+2.8

2018...+0.8...+0.8...+1.7

2017...+7.2...+7.2...+7.4

2016...+2.3...+1.9....+3.1

2015...+0.6...+1.1....+0.3

2014...+2.7...+2.7....+2.2

2013...+3.0....+3.3...+2.8

2012...+2.2....+1.1....+1.9

2011...+1.5...+0.2.....+0.2

2010...+1.7...+1.2....+2.1

 

[donsutherland1]

Morning thoughts...

Today will be unseasonably warm today. Temperatures will likely reach the lower and middle 70s. Likely high temperatures around the region include:

New York City (Central Park): 72°
Newark: 76°
Philadelphia: 75°

A system could bring some rain tomorrow followed by a brief shot of noticeably cooler air.

[the_other_guy]

3 hours ago, bluewave said:

GEFS in full cold bias correction mode as its seeing the stronger WAR pattern. Tough to bet against those very warm SSTs to our east. This is how a -5 forecast for the start of the month turned into a +1 to +3.

 

 

Amazing that just N and W of Manhattan has a much smaller departure from normal than Central LI.

 

I wonder if that holds going forward towards winter

[Stormlover74]

Looks like a nice weekend on tap. Nam gets the rain out of here well before midnight now

[Brian5671]

15 minutes ago, jfklganyc said:

Amazing that just N and W of Manhattan has a much smaller departure from normal than Central LI.

 

I wonder if that holds going forward towards winter

less marine influence there.   Close to 80 degree water for a time this summer which has only slowly cooled off

[Brian5671]

40 minutes ago, Stormlover74 said:

Looks like a nice weekend on tap. Nam gets the rain out of here well before midnight now

The old adage will apply-earlier to start earlier to finish.   Happens alot with these fast moving storms-this one is more like a frontal wave vs the storm some models had earlier in the week.

[FPizz]

23 hours ago, LibertyBell said:

why dont they fix this cold bias?  Isn't this as simple as applying a positive (+) temperature correction to the data?  Simply do a study to see what the magnitude of the cold bias is and adjust the model to account for it?

 

During the summer it also spits out 100s like it is its job in the long range.  I think for Philly at day 7+ it spit out 100s over 20x this summer.  Their high temp for the summer was 97.

[Allsnow]

3 hours ago, FPizz said:

During the summer it also spits out 100s like it is its job in the long range.  I think for Philly at day 7+ it spit out 100s over 20x this summer.  Their high temp for the summer was 97.

Yes, In  the summer it never saw a heat wave it didn’t like. It has a warm bias in the summer. 

[Stormlover74]

1 hour ago, Brian5671 said:

The old adage will apply-earlier to start earlier to finish.   Happens alot with these fast moving storms-this one is more like a frontal wave vs the storm some models had earlier in the week.

Now we throw in the gfs 2"+ and the rgem mostly around .5"

[Brian5671]

3 minutes ago, Stormlover74 said:

Now we throw in the gfs 2"+ and the rgem mostly around .5"

Outlier.  Most models are around .5 to .75

[SnoSki14]

6 hours ago, bluewave said:

GEFS in full cold bias correction mode as its seeing the stronger WAR pattern. Tough to bet against those very warm SSTs to our east. This is how a -5 forecast for the start of the month turned into a +1 to +3.

We're really feeling the AGW effects now. 

It seems as though 2015/2016 was a tipping point with the mega Nino. I think every winter from this point on will be warm/wet or warm/dry.

Snow will be unlikely but not impossible as years like 2016/2017 could still happen. 

However this year will likely be another 2011/2012 style winter.

[Brian5671]

1 hour ago, SnoSki14 said:

We're really feeling the AGW effects now. 

It seems as though 2015/2016 was a tipping point with the mega Nino. I think every winter from this point on will be warm/wet or warm/dry.

Snow will be unlikely but not impossible as years like 2016/2017 could still happen. 

However this year will likely be another 2011/2012 style winter.

11-12 featured a big PV like last year but was bone dry. Also had some big solar storms that fall that I wonder if they had an influence?     Doubt we see anything that dry this year.  Last year had the big PV but it was wetter, just zero cold air with the PV locked away.

[binbisso]

6 hours ago, bluewave said:

We are on track for an 11th consecutive warmer than normal October.

 

 

Oct.......EWR...NYC...LGA

2020..+1.0...+0.9....+1.6...through the 14th

2019..+3.8...+3.0 ...+2.8

2018...+0.8...+0.8...+1.7

2017...+7.2...+7.2...+7.4

2016...+2.3...+1.9....+3.1

2015...+0.6...+1.1....+0.3

2014...+2.7...+2.7....+2.2

2013...+3.0....+3.3...+2.8

2012...+2.2....+1.1....+1.9

2011...+1.5...+0.2.....+0.2

2010...+1.7...+1.2....+2.1

 

That's pretty amazing how one month can be consistently warmer then normal for so long what's interesting when looking at the departures, this October should be very close to 2010 when looking at the current long-range guidance. 2010 also had an amplified mjo in Phase 5 as you stated in the other thread and it looks quite similar. 

[bluewave]

36 minutes ago, binbisso said:

That's pretty amazing how one month can be consistently warmer then normal for so long what's interesting when looking at the departures, this October should be very close to 2010 when looking at the current long-range guidance. 2010 also had an amplified mjo in Phase 5 as you stated in the other thread and it looks quite similar. 

September is right up there also. But this fall so far is less warm than recent years. 

 

SEP....EWR...NYC...LGA

2020...+0.9....+0.8....+2.0

2019...+2.6....+2.4....+3.0

2018...+3.2...+2.7....+3.7

2017...+2.7...+2.5....+2.4

2016...+3.6...,+3.8...+4.7

2015...+5.2....+6.5...+5.0

2014..+1.6....+1.7....+1.3

2013...-1.0....-0.1.....-1.0

2012...+1.3...+0.8....+3.4

2011....+3.0..+2.0....+1.6

2010...+3.4....+3.1...+3.4

 

[donsutherland1]

A slow-moving cold front will move across the region tomorrow and tomorrow night. At the same time, low pressure will develop and move northward along that front. As a result, tomorrow will be breezy, with periods of rain, and noticeably cooler temperatures. A general 0.50"-1.50" rain, with lighter amounts from New York City and westward and higher amounts over eastern New England is likely. A few parts of northern New England and southern Quebec could pick up 2" or more precipitation.

In the wake of the cold front, a chilly weekend is in store. However, temperatures will likely return to normal and above normal conditions early next week. This warmth will likely persist through the remainder of next week.

The ENSO Region 1+2 anomaly was -1.2°C and the Region 3.4 anomaly was -1.2°C for the week centered around October 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.92°C and the ENSO Region 3.4 anomaly has averaged -1.00°C. La Niña conditions will likely prevail into at least the start of winter.

The SOI was -7.29.

Today, the preliminary Arctic Oscillation (AO) figure was -0.946.

On October 14 the MJO was in Phase 4 at an amplitude of 2.346 (RMM). The October 13-adjusted amplitude was 1.986.

Since 1950, there have been five cases where a La Niña developed during June-July-August or afterward following an El Niño winter. 4/5 (80%) of those cases saw a predominant EPO+/AO+ winter pattern. The most recent such case was 2016-17. 9/10 (90%) of the La Niña winters that followed an El Niño winter featured a predominantly positive EPO.

In addition, from the larger pool of La Niña winters following El Niño winters, there were four cases where October saw the MJO in Phases 4-6 for 20 days or more: 1983-84, 1988-89, 1998-99, and 2016-17. All four cases featured an EPO+/AO+ winter. Three cases saw the MJO in Phases 4-6 for less than 20 days: 1995-96: 12 days, 2007-08: 6 days, and 2010-11: 6 days. Both 1995-96 and 2010-11 featured a predominantly negative AO. The latest ensemble guidance favors October 2020 falling into the former pool.

Based on sensitivity analysis applied to the latest guidance, there is an implied 72% probability that New York City will have a warmer than normal October. October will likely finish with a mean temperature near 58.5°.   

Finally, the NOAA released its annual winter outlook, which can be found here: https://www.noaa.gov/media-release/us-winter-outlook-cooler-north-warmer-south-with-ongoing-la-nina

 

 

[jm1220]

5 hours ago, SnoSki14 said:

We're really feeling the AGW effects now. 

It seems as though 2015/2016 was a tipping point with the mega Nino. I think every winter from this point on will be warm/wet or warm/dry.

Snow will be unlikely but not impossible as years like 2016/2017 could still happen. 

However this year will likely be another 2011/2012 style winter.

Every winter from here on out won’t be warm and snow unlikely. That’s ridiculous. 

We were due for a lousy stretch of winters after so many above normal since 2000. We’ve had many stretches like this in the past-much of the 1980s and late 1990s were awful. I’m hopeful we somehow make it to normal but I’m not optimistic for this season either. Doesn’t mean we’re somehow shut out permanently. If the NAO/AO cooperate, PNA, EPO etc we can be very snowy. 

[the_other_guy]

2 hours ago, jm1220 said:

Every winter from here on out won’t be warm and snow unlikely. That’s ridiculous. 

We were due for a lousy stretch of winters after so many above normal since 2000. We’ve had many stretches like this in the past-much of the 1980s and late 1990s were awful. I’m hopeful we somehow make it to normal but I’m not optimistic for this season either. Doesn’t mean we’re somehow shut out permanently. If the NAO/AO cooperate, PNA, EPO etc we can be very snowy. 

I think the analysis is a little melodramatic, but he is onto something about that El Nino. It was scary warm that December and something seems to have snapped. Since then, extreme warmth at several points in the winter is the new normal.

When was the last time we had a prolonged stretch with snow on the ground? Our snow has become like Denver...a dump and a rapid melt. Historically, that hasnt been the case in NYC.

We shall see if this pattern sticks, but the warmth wont let up. Even our cool months like this fall are still AN

[USCG RS]

8 hours ago, SnoSki14 said:

We're really feeling the AGW effects now. 

It seems as though 2015/2016 was a tipping point with the mega Nino. I think every winter from this point on will be warm/wet or warm/dry.

Snow will be unlikely but not impossible as years like 2016/2017 could still happen. 

However this year will likely be another 2011/2012 style winter.

Um?

[SACRUS]

10/15

EWR: 77
New Brnswck: 76
BLM: 75
TEB: 75
PHL: 75
TTN: 74
ACY: 73
LGA: 73
NYC: 71
JFK: 70
ISP: 69

[CIK62]

The next 8 days are averaging 63degs.     Making it 58degs., or about +2.0.      It actually has 6 70-Degree Days in a row upcoming, after brief BN cameo.      EURO ditto to 5 70-Degree Days.     I have to question the signing to a leading role by the GFS of BN for a final October week opening.  Lol.

1.3" to 2.0" today into early Saturday.

64*(96%RH) here at 6am.     Down to 55*(95%RH) by Noon as rain came in during last few hours.       53*(91%RH) by 5pm.      52*(92%RH) by 10pm.

[wdrag]

Good Friday morning everyone,

No topic for me on todays rainfall... helpful for sure. Am expecting basically 1/2 to 2" depending on repeat episodes of showers. Note impossible to see 2.5" but to me this is relatively normal.  

I am paying attention to the pattern around October 25-27.  Zeta (my expectation only-if the earlier near Bermuda system ~10/20-22 doesn't get named Epsilon, then I suspect the FL system around 24th-25th would be Epsilon). We'll see if the 500 MB pattern adjusts to a sharper trough near 80-85W longitude as the EPS is starting to show recently. If not, then no problem. NAEFS shows something along the se USA coast then peeling out to sea northeastward. VERY VERY early (9 days) but based on multi op models and multiple ensembles, am glad am not cruising Bermuda to Key West...I think its going to be a little on the rough side as opposed to typical daily tropical.   Again, only what I'm looking for. It still may not pan out. 654A/16